Device for driving or stopping a driven shaft



May 8, 1956 H. K. KOHLER ETAL DEVICE FOR DRIVING OR STOPPING A DRIVEN SHAFT Filed Oct. 14, 1953 5 Sheets-Sheet 1 May 8, 1956 H. K. KOHLER ETAL DEVICE FOR DRIVING OR STOPPING A DRIVEN SHAFT Filed Oct. 14, 1953 5 Sheets-Sheet 2 Mam INVENTORS Hell/n71 Va rZ M4341:

Han; Vall'aw 5414410,

N L'MI/M 'L ff/aru May 8, 1956 H. K. KOHLER ETAL DEVICE FOR DRIVING OR STOPPING A DRIVEN SHAFT Filed Oct. 14, 1953 3 Sheets-Sheet 3 United States Patent O DEVICE FOR DRIVING OR STOPPING A 1 DRIVEN SHAFT Application October 14, 1953, Serial No. 385,992

5 Claims. (Cl. 192-148) This invention relates to a device for driving or stopping a driven shaft supporting a drum of a counting mechanism for bookkeeping machines and the like.

In a known device of this class the position of rest of the driven shaft is determined by a stop shaft arranged in front of it, the stops or contacts of which being subject to control and manual selection. This device consists of a lever fitted with a pin secured to the stop shaft, and on a lever of the driven shaft a coupling pawl is moved by a circular catch plate which is provided with a slot guide engaged by the pin of the lever arranged on the stop shaft. When this shaft is arrested by stops or contacts the driven shaft continues to move a certain distance, a spring disposed between the two levers is tensioned and the slot guide and the pin cooperate to lift the coupling pawl out of the catch plate. After release of the stops or contacts the tension spring draws the parts back into the previous position, so that the coupling pawl can resume its previous position and the device begins to move again. In this device the driven shaft is driven at the same speed as the motor-driven circular catch plate until the coupling pawl is disengaged. The rotating mass or drum of the counting mechanism keeps going and urges the driven shaft, until the tension of the spring arrests and swings back the shaft which comes to a standstill only after the rotating mass and the spring have ceased to oscillate. When a drum of the counting mechanism is arranged on the driven shaft this oscillation causes errors in calculationor jamming of the machine. To avoid this latter trouble the running of the machine must be so timed that the counting mechanism becomes engaged only after the driven shaft has stopped moving, which involves a considerable loss of time. To shorten this movement the tension spring located between the two levers is made as strong as possible, but this causes hard impacts and may lead to damage to the material or machine.

It is the object of the invention to provide a simple device of this kind operating more safely in spite of increased speed and being free from the drawbacks mentioned. This is attained by arranging between the stop and driven shafts camlike and/ or hingelike coacting parts which positively retard the driven shaft and subsequently "the driven shaft stopped.

To a stop shaft 2 arranged in a bearing member 1 stop 2,744,600 Patented May 8, 1956 posed on the shaft 2 is provided by riveting on one side with a gear 5 and on the other with a circular catch plate 6, the gear 5 being driven by a motor (not-f shown) of the machine in the direction of the arrow. A guide lever 7 fixed by pins to the shaft2 and provided with an angle 8 supports two spring pins 9, 10, a bearing bolt 11 on which a roller 12 moves, and a pin 13. A driven shaft 14 of which the shaft 2 is an extension is arranged in the bearing 15, and a lever 16 secured to the shaft 14 is fitted with two spring pins 17, 18 which by means of the tension springs 19, 20 effect non-positive connection to the spring pins 9, 10 of the guide lever 7.

On a bearing bolt 21 fastened to the lever 16 a cam member 22 is rotatably disposed and provided with a curved groove 23 overlapping the roller 12 of the guide lever 7 and constructed so that its portion 24 extends radially to the turning point of driven shaft 14 and its other portion 25 radially to the turning point of the cam member 22 and the transition proceeds in archlike fashion. On the lever 16 a spring pin 26 and on the cam member 22 a spring pin 27 are arranged, and a tension spring 28 disposed between these two parts tends to draw the cam member 22 into the position shown in Fig. l. The cam member22 is also provided with a bearing bolt 29 supporting a rotatable coupling pawl 30 fitted with a catch 31, an arresting angle 32, a spring arm 33 and an arresting pawl 34 drawn by a tension spring 35 suspended between a spring pin 36 disposed on the pawl 34 and a spring pin 37 positioned on the cam member 22. Another tension spring 38 provided between the spring arm 33 of the coupling pawl 30 and the spring pin 37 of the cam member 22 tends to draw the nose 31 of the pawl 30 into grooves 39 on the circumference of the circular catch plate 6. The arresting pawl 34 can engage the angle 32 of the pawl 30 when the latter is lifted out of the grooves 39, and the angle 8 of the guide lever 7 can effect disengagement thereof after release of. the shaft 2. A stationary detent 40 drawn by a tension spring 41 engages a ratchet wheel 42 secured to the driven shaft 14 and thus prevents turning in a direction opposite to that indicated by the arrow.

On a stationary shaft 43 a corresponding number of stop members 44 are provided to act as stops for the stop levers 3, each member 44 being connected in hingelike manner with an intermediate member 45 connected in the same manner to a toggle 46. The toggles 46 are rotatably disposed on a stationary shaft 47 and drawn against a stationary shaft 49 by means of tension springs 48. At the actuation of a toggle 46 the knee places a nose 50 in the path of the coacting stop lever 3 and on being straightened is stopped by the bar 51.

As shown in Figs. 3 and 4 illustrating a second example of construction, the cam member 22 is replaced by a rotatable retarding lever 52 positioned on the bearing bolt 21 of the driven lever 16. The bearing bolt 11 of the guide lever 7 is provided with a movable member 53 stoppable by the pin 54. The retarding lever 52 and the member 53 are articulated by means of the rivet 55. The parts shown on the cam member 22 in Figs. 1 and 2 are arranged in like manner on the retarding lever 52.

The mode of operation of the device shown in the first example is as follows:

If none of the levers 3 is held by the stop members 44 the tension springs 19, 20 pull the stop shaft 2 far enough relative to the driven shaft 14 to enable the roller 12 of the guide lever 7 to occupy the portion 24 of the groove 23, as indicated in Fig. 1. In this position the angle 8 of the lever 7 has moved the arresting pawl 34 so far that the coupling pawl 30 drawn by the tension spring 38 engages with its catch 31 a groove 39 of the circular catch plate 6, the grooves 39 being so constructed as to arrest the pawl 30 in both turning directions. As the circular catch plate 6 is continually driven in the direction of the arrow by a drive not shown, both shafts 2, 14 are set in motion in the direction of the arrow via the pawl 30, cam member 22 and the roller 12 of the guide lever 7, which prevents turning of the cam member 22.

The stop shaft 2 is driven until the corresponding lever 3 is stopped by the nose 50 of the member 44 with the aid of the intermediate member 45 and toggle 46. Owing to the stopping of the shaft 2, the guide lever 7 fastened thereto as well as the roller 12 come to a standstill while the pawl 30, cam member 22 and driven shaft 14 continue to move. During the first part of this movement the cam member 22 keeps rolling in the portion 24 radially extending to the turning point of the driven shaft 14, so that it does not turn on its bearing bolt and the speed is therefore the same as that of the catch plate 6. When during further motion the cam member 22 with the archlike portion of its curved groove rolls over the roller 12 it turns on its bearing bolt 21, whereby the speed of this bolt and thus that of the lever 16 fixed to the driven shaft 14 is reduced, and when the portion 25 of the groove 23 passes over the roller 12 this retardation finally leads to the stopping of the shaft 14, since the portion 25 of the groove extends radially to the turning point of member 22.

This positive stopping operation is explainable as follows: After the shaft 2 has been stopped, the cam member 22, during its further motion, turns on its bearing bolt 21.

If the driven shaft 14 were to retain the same speed it would have to accelerate the catch plate 6, because the movement of the cam member 22 accelerates the coupling pawl 30. As, however, always the same speed is imparted to the catch plate 6 by the drive and this plate arrests the pawl in both directions of motion, this play of levers must lower the speed of the driven shaft 14 and effect the stopping thereof. When the portion 25 of the curved groove 23 slides over the roller 12 the coupling pawl 30 is lifted out of the groove 39 of the plate 6 by running with its inclined face 56 on the pin 13 of the guide lever 7. Before the pawl 30 leaves the groove 39 the arresting pawl 34 movably disposed on the cam member 22 engages the angle 32 of the pawl 30, due to the opposite movement of both parts, whereby the pawl 30 is held in position. The cam member 22 is then swung back about the portion 25 by the tension spring 28, whereby the pawl 30 is moved out of the groove 39. To prevent the driven shaft 14 from coming back a locking pawl 40 engages a ratchet wheel 42 secured to the shaft. change of stops the shaft 2 is released, and the tension springs 19, 20 arranged between the guide lever 7 and lever 16 draw the shaft 2 along to the extent of the further motion made by the driven shaft 14. The roller 12 thus enters portion 24 of the curved groove 23 and, simultane- 1 ously, the angle 8 of the guide lever 7 by moving the arresting pawl 34, releases the coupling pawl 30. Then follows the same operation as previously described.

In the second example shown in Figs. 3 and 4 the device operates in all its functions exactly as in the first one with the exception of the cam member 22 and the roller 12. They are replaced by a retarding lever 52 arranged on the bearing bolt 21 of the lever 16 and rotatably connected by a rivet with a member 53 movably disposed on the guide lever 7. In driving position of the device turning of the retarding lever 52 supporting the coupling pawl 30 is prevented, since (Fig. 3) the rivet 55 is disposed above the connecting line of the bolt 11 of the guide lever 7 with the turning point of shaft 2. When the latter is stopped as described the retarding lever 52 is driven still farther by the pawl 30. The initial motion of lever 52 on its bearing bolt 21 is slight, but increases more and more, due to continued driving of the pawl 30, until, owing to the straightening of the member 53 and of one of the Ata' to a standstill. By this increasing motion of the retarding lever 52 on its bearing bolt 21 the same reduction of speed of the driven shaft 14 as in the first example and thereby positive stopping thereof is attained. When the stops are changed the tension spring 28 pulls the hinge members 52, 53 into the position shown in Fig. 3, whereupon driving occurs again.

We claim:

1. Device for actuating and stopping a driven shaft carrying the drum of a counting mechanism for bookkeeping machines and the like, comprising, in combination, a stop shaft forming an extension of the driven shaft and determining the position of rest thereof, a plurality of stops on the stop shaft to stop it in different positions, a circular catch plate circumferentially grooved at intervals and rotatably arranged on the stop shaft, a lever secured to the driven shaft, a bearing bolt for the lever, a grooved cam member rotatably disposed on said bearing bolt, a coupling pawl rotatably positioned on the cam member and possessing an inclined portion, means provided on the cam member to draw the nose of the pawl into grooves of the circular catch plate, said grooves being constructed to hold the nose against rotation in both directions, a guide lever fastened to the stop shaft, a roller supported by the guide lever and overlapped by the cam groove, said groove having a portion extending radially to the turning point of the driven shaft and another portion extending radially to the turning point of the cam member and the transition occurring in archlike fashion.

2. Device according to claim 1, in which the means drawing the nose of the pawl into a groove of the circular catch plate consists of a tension spring by the engagement of which with the groove the driven shaft is driven by way of the cam member and the lever secured to the driven shaft, turning of the cam member on its bearing bolt being prevented by the roller of the guide lever, and at the standstill of the stop shaft and roller the coupling pawl is driven further and thereby causes again turning of the cam member, and in which a pin is provided on the guide lever and engaged by the inclined portion of the pawl to effect lifting of the pawl out of the groove of the catch plate, an arresting angle is disposed in a continuation of the pawl, a springy arresting pawl on the cam member engages the angle, a spring is arranged between the cam member and the lever of the driven shaft to swing back the cam member after the nose of the coupling pawl has been lifted out of the groove of the catch plate and thereby keeps it away from the grooves thereof, a ratchet wheel is secured to the driven shaft and a spring-actuated stationary locking pawl engages the ratchet wheel to prevent turning of the driven shaft.

3. Device according to claim 1, in which the means drawing the nose of the pawl into a groove of the circular catch plate consists of a tension spring by the engagement of which with the groove the driven shaft is driven by way of the cam member and the lever secured to the driven shaft, turning of the cam member on its bearing bolt being prevented by the roller of the guide lever, and at the standstill of the stop shaft and roller the coupling pawl is driven further and thereby causes again turning of the cam member, and in which a pin is provided on the guide lever and engaged by the inclined portion of the pawl to effect lifting of the pawl out of the groove of the catch plate, an arresting angle is disposed in a continuation of the pawl, 21 springy arresting pawl on the cam member engages the angle, a spring is arranged between the cam member and the lever of the driven shaft to swing back the cam member after the nose of the coupling pawl has been lifted out of the groove of the catch plate and thereby keeps it away from the grooves thereof, a ratchet wheel is secured to the driven shaft, a spring-actuated stationary locking pawl engages the ratchet to prevent turning of the driven shaft and tension springs are arranged between the guide lever and the lever of the arms of the lever (Fig. 4), the driven shaft 14 is brought stop shaft to sufficiently pull the guide lever relative to the lever of the stop shaft to position the roller of the guide lever in the portion of the cam groove extending radially to the turning point of both the driven and stop shafts.

4. Device according to claim 1, in which each of the stop members comprises three hingelike parts and the part executing the stopping action is brought into position by the straightening of the two other parts.

5. In a device for actuating and stopping a driven shaft bearing bolt, a guide lever fastened to the stop shaft, a coupling pawl disposed on the retarding lever, a movable member positioned on the guide lever, and by riveting rotatably connected to the retarding lever, said movable member, at driving position of the device, being in a position preventing turning of the retarding lever on its bearing bolt, said coupling pawl, at a position of rest of the stop shaft, moving the retarding lever at increasing speed on its bolt to reduce the speed of the driven shaft carrying the drum of a counting mechanism for bookkeepl0 and positively stop it.

ing machines and the like a stop shaft forming an extension of the driven shaft and determining the position of rest thereof, a plurality of stops on the stop shaft to stop it in difierent positions, a circular catch plate circumferentially grooved at intervals and rotatably arranged on the 15 stop shaft, a lever secured to the stop shaft, a bearing bolt arranged on the lever, a retarding lever disposed on the May Feb. 19, 1952 Gardinor et al Apr. 7, 1953 

